CV Alpha Blockers

Question 1

What are examples of Alpha blockers?

Answer 1

1. Doxazosin
2. Tamsulosin
3. Alfuzosin

Question 2

Indications for Alpha blockers?

Answer 2

1. Benign Prostatic hyperplasia (BPH)

2. Add on treatment in resistant hypertension

Question 3

What is the mechanism of action of alpha1 blockers?

Answer 3

1. Highly selective for the alpha1 adrenoreceptor
2. Alpha1 adrenoreceptors found in smooth muscle
3. Stimulation=contraction, blockade = relaxation
4. Alpha1 blockers cause vasodilation. Reduce resistance to bladder outflow.

Question 4

adverse affects of alpha1 blockers?

Answer 4

1. Postural hypotension
2. Dizziness
3. Syncope
4. Prominent after first dose
5. Should not be used in patients with postural
   hypotension

Question 5

Practical Prescribing?

Answer 5

1. Doxazosin licensed for BPH and Hypertension
2. Tamsulosin just for BP
3. Normally taken at bedtime

Question 6

Prescribing?

Answer 6

1. Doxazosin 1mg then inc at 1-2 week intervals

2. Tamsulosin - 400mcgs daily